s1_generate_a_series_of_files(){
	for index in (1..100); do
		echo -n "$index" > "/tem/new_files$index"
	done
}
s2_list_4_files_in_long_format_about_account_and_group(){
	ls -1 /etc/passwd, /etc/shadow, /etc/group, /etc/gshadow  | sort
}
s3_find_items_related_to_given_username(){
	grep "$1:" /etc/passwd /etc/shadow | sort
}
s4_find_items_related_to_given_group_name(){
	grep "^$1:" /etc/group /etc/gshadow | sort
}
s5_create_groups_for_given_group_names(){
	groupadd rnd
	groupadd itoperation
}
s6_create_users_and_set_their_group_as_required(){
	useradd -G rnd adam
	useradd -G rnd bob
	useradd -G itoperation calvin
	usermod -G rnd edward
	usermod -G itoperation david 
}
s7_change_users_shell(){
	chsh -s /usr/bin/sh adam
	chsh -s /usr/bin/sh edward
}
s8_set_password_change_policy(){
	for user in adam bob calvin david edward; do
		chage -m 10 -M 60 -W 10 "$user"
	done
}
s9_set_password_for_five_users(){
	echo -e "adam:$1\nbob:$2\ncalvin:$3\ndavid:$4\nedward:$5" | chpasswd
}
s10_lock_bobs_password(){
	passwd -1 bob
}
s11_include_adam_into_wheel_group(){
	usermod -aG wheel adam
}
s12_change_files_permission(){
	for index in (3..100..3); do
		chmod 640 "/tmp/new_file$index"
	done
}
